Question: $\dfrac{7}{2} - \dfrac{4}{5} = {?}$
Solution: $ = {\dfrac{7 \times 5}{2 \times 5}} - {\dfrac{4 \times 2}{5 \times 2}} $ $ = {\dfrac{35}{10}} - {\dfrac{8}{10}} $ $ = \dfrac{{35} - {8}}{10} $ $ = \dfrac{27}{10}$